Mean Free Path of Electrons and Magnetomorphic Effects in Small Single Crystals of Gallium

M. Yaqub; J. F. Cochran

doi:10.1103/physrev.137.a1182

Thermal Conductivity of Single-Crystal and Sintered RBa2Cu3O7 at low Temperatures

MRS Proceedings ◽

10.1557/proc-99-745 ◽

1987 ◽

Vol 99 ◽

Cited By ~ 5

Author(s):

J. E. Graebner ◽

L. F. Schneemeyer ◽

R. J. Cava ◽

J. V. Waszczak ◽

E. A. Rietman

Keyword(s):

Thermal Conductivity ◽

Particle Size ◽

Single Crystals ◽

Free Path ◽

Low Temperatures ◽

Rayleigh Scattering ◽

Resonant Scattering ◽

Sintered Sample ◽

Mean Free Path ◽

Strong Scattering

ABSTRACTThe thermal conductivity k of micro-twinned single crystals of YBa2Cu3O7 and HoBa2Cu3O7 and a sintered sample of YBa2Cu3O7 has been measured for temperatures 0.03<T<5K. For the single crystals, k is small and varies as T1.8-1.9 This behavior resembles k for glassy insulators except for the lack of a plateau above IK. It is concluded that the thermal carriers are phonons with their mean free path limited by resonant scattering from tunneling entities, as in glasses. Suggestions for the location of tunneling systems are given. For the sinter, k is still smaller but does not follow a power law T-dependence. It is similar to other sintered ceramics with the same particle size, where the phonon mean free path is dominated by Rayleigh scattering from the particles. This strong scattering from the microstructure presumably masks the scattering from TS within each particle.

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The mean free path of mobile dislocations in doped NaCl single crystals measured by N.M.R. between room temperature and 300°C

Philosophical Magazine A ◽

10.1080/01418618208239572 ◽

1982 ◽

Vol 46 (3) ◽

pp. 469-481 ◽

Cited By ~ 6

Author(s):

W. H. M. Alsem ◽

J. Th. M. De Hosson ◽

R. Muenter ◽

H. Tamler ◽

O. Kanert

Keyword(s):

Single Crystals ◽

Free Path ◽

Room Temperature ◽

Mean Free Path ◽

The Mean

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Thermal Conductivity of Gel-Grown Barium Oxalate at 326 and 335 K

Journal of Soft Matter ◽

10.1155/2013/162428 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4

Author(s):

Paresh Vasantlal Dalal

Keyword(s):

Thermal Conductivity ◽

Ambient Temperature ◽

Single Crystals ◽

Free Path ◽

Grown Crystal ◽

Mean Free Path ◽

Monoclinic Structure ◽

Agar Gel ◽

Gel Method ◽

Barium Oxalate

Single crystals of barium oxalate have been grown by gel method using agar-agar gel as media of growth at ambient temperature. The grown crystal crystallizes under monoclinic structure. Thermal conductivity of gel-grown barium oxalate crystals as a function of temperature has been studied at 326 and 335 K by using divided bar method. The thermal conductivity of barium oxalate crystal at 326 K was found 3.685 W m−1 K−1 and 3.133 W m−1 K−1 at 335 K. The reduction of thermal conductivity with the rise in temperature may be due to reduction in mean free path of phonons in the solid.

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Flux pinning mechanism in BaFe1.9Ni0.1As2 single crystals: Evidence for fluctuation in mean free path induced pinning

Applied Physics Letters ◽

10.1063/1.4813113 ◽

2013 ◽

Vol 103 (3) ◽

pp. 032605 ◽

Cited By ~ 22

Author(s):

M. Shahbazi ◽

X. L. Wang ◽

K. Y. Choi ◽

S. X. Dou

Keyword(s):

Single Crystals ◽

Free Path ◽

Flux Pinning ◽

Mean Free Path ◽

Pinning Mechanism

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Synthesis and Thermoelectric Properties of NaxCo2O4 Single Crystals

MRS Proceedings ◽

10.1557/proc-0886-f02-04 ◽

2005 ◽

Vol 886 ◽

Author(s):

Jian He ◽

Kelvin Aaron ◽

Edward Abbott ◽

Joseph Kolis ◽

Terry M. Tritt

Keyword(s):

Thermal Conductivity ◽

High Temperature ◽

Low Temperature ◽

Single Crystal ◽

Temperature Dependence ◽

Single Crystals ◽

Free Path ◽

Mean Free Path ◽

Flux Method ◽

Different Types

ABSTRACTSingle crystal NaCo2O4 platelets with sizes up to 6mm were synthesized by the typical high temperature NaCl flux method. The in-plane thermopower α and in-plane resistivity ρ were measured to be ∼100µV/K and 0.3mΩ-cm at 300K, respectively. The in-plane thermal conductivity κ was measured by our custom-designed “PTC” system and found to be ∼5 W-m−1K−1 at 300K, which is 2-3 times larger than the polycrystalline NaCo2O4. The in-plane phonon mean free path lph was estimated to be ∼9.5Å, which is much smaller than the in-plane mean free path of conducting carriers (la∼51Å). A novel low temperature flux method where NaCl/NaOH was used as flux and metallic Co powders as Co source was developed to successfully synthesize Na-deficient NaxCo2O4 crystals with size up to 6mm at low temperature of 550°C. The different temperature dependence in resistivity reveals that two different types of crystals can exist, one is metallic and another is semiconducting. The temperature dependence of the measured k is like that of a disordered solid and the value is found to be ∼7 W-m−1K−1 at 300K.

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